In the U.S., we are living in the Varietal Wine Age, like all of the other New World (non-European) countries. Most of the wines we make and drink have varietal names, such as Chardonnay, Cabernet Sauvignon, Merlot, Pinot Noir, Zinfandel, Syrah/Shiraz, and Sauvignon Blanc--USA's most popular seven.
But I'm seeing a new trend in wine drinking in this country in the 
21st century. Restaurants and retail stores are starting to carry non-mainstream varietal wines, which hail primarily from their original home, Europe--especially Italy, France, and Spain. Where have these 'new' grape varieties been? They've existed all along, of course. It's just that most American wine drinkers weren't ready to experiment with grape varieties that they did not know.
But a new spirit of adventure seems to pervade the wine scene in 
the U.S. lately, and I, for one, am pleasantly surprised and happy to find varietal wines such as Kerner, Grignolino, Albariño, Lagrein, Tempranillo, Malbec, Carmenère, Moschofilero, Grüner Veltliner, Fiano, Torrontés, Müller-Thurgau, Nero d'Avola, Petite Sirah, Petit Verdot, Viognier, Blaufränkisch, and many others on restaurant wine lists. What a treat! I'm not even counting Riesling, Gewürztraminer, Chenin Blanc, and Cabernet Franc, which have been here all along, just under-used and under-appreciated.
Varietal wines are a relatively new phenomenon in the wine world. Most European wines are traditionally named after the place they come from, such as Bordeaux, Barolo, Burgundy, Champagne, Chianti, and so forth. But varietal wines have also existed in some places in Europe for a long time; for instance, Germany and Alsace have had their Riesling, Gewürztraminer etc. and Italy has produced many varietal wines, such as Barbera, Dolcetto, Aglianico, and many others.
In the United States, varietal wines were practically unheard of until the 1960s. Instead, we had wines with contrived, colorful names, such as Vino Rustico, or we borrowed wine names from Europe, such as Burgundy, Chianti, Chablis, Rhine Wine, and "Sauterne"--wines made from obscure, inexpensive varieties (such as French Colombard) which had no relation at all to wines from the places from which they were named.
And then we came of age, as a wine country. The late Robert Mondavi is generally credited with ushering in the Varietal Wine Age in the U.S., when he opened up Robert Mondavi Winery in 1966 with the expressed purpose of making 'better' wines, and started producing Cabernet Sauvignon, Chardonnay, and Fumé Blanc (Mondavi's name for Sauvignon Blanc). The wines received good reviews, caught on with American wine buyers, and almost overnight, it seemed that all American wine producers were making varietal wines! But they mainly stuck to the popular varieties of the time.
Today, many wine producers in the U.S. are making varietal wines that no one in this country had ever heard of 40 years ago. And we now have a rich display of European varietal wines available here, led by Italy--which has far more grape varieties (over 2,000) than any other country in the world.
I have compiled a list of 'non-mainstream' varieties, 31 white and 35 red, which I believe are 'happening' varieties or about to happen. I give a brief description of the varietal wine made from the variety, other names that the variety is known by (if any), and the country of origin. Some of these varieties have been in the U.S. for a while, but might not have achieved 'stardom' here yet. Other varieties most wine drinkers might not have heard of, but I'm betting that they will, soon.
I list the varieties alphabetically. Please forgive me if I've left out your favorite variety, but the list is nearly endless!
Albariño, a.k.a. Alvarinho (Galicia, Spain)--aromatic, crisp, medium-bodied; resembes Riesling and Viognier; usually made as an unoaked wine.
Aligoté (Burgundy, France)--light, very lively, with lots of acidity; the base wine used in kir, a popular French cocktail made with cassis.
Arneis (Piedmont, Italy)--light-to medium-bodied, viscous, with floral aromas and suggestions of pears and almonds; also grown in California and Oregon.
Assyrtiko (Santorini, Greece)--pronounced ah SEER tee koe; minerally, with lots of acidity; very dry, long-lived wines. Greece's best white variety.
Chasselas, a.k.a. Fendant (Switzerland)--light-bodied, flowery, honeyed; makes a light, unoaked wine; also in Loire Valley and Baden, Germany. Considered the oldest known grape variety, with possible origins in Egypt 5,000 years ago.
Cortese (Piedmont, France)--crisp, very dry, light-bodied. In Italy, it makes the popular Piedmontese white wine, Gavi. Best when it's young. Also grown in California.
Fiano (Campania, Italy)--medium-bodied, with aromas of pears and hazelnuts; its origins traced back to Roman Age; makes long-lived wines. Best white wine in Campania; leading example: Fiano di Avellino. Also grown in California.
Friulano, formerly Tocai Friulano (Friuli and Veneto, Italy)--Friuli's most popular white variety is believed to have originated in neighboring Veneto. Medium-bodied, viscous, flowery. Also grown in California.
Furmint (Hungary)--Best-known as the main variety in Hungary's great dessert wine, Tokaji, Furmint also is a dry, viscous, medium-bodied white wine.
Garganega (Veneto, Italy)--delicate, bitter almond, citric aromas; the basic variety used in Soave wines.
Grechetto (Umbria, Italy)--floral, lemony, quite flavorful; a main component of Orvieto wine, but also made as a varietal wine in central Italy.
Greco (Southern Italy)--dry, spicy, medium-bodied; of Greek origin. Grown throughout southern and central Italy; in Campania, makes a wine known as Greco di Tufo.
Grillo (Sicily, Italy)--crisp, dry, full-bodied. Formerly used exclusively for blending; now being made as a varietal wine.
Grüner Veltliner (Austria)--dry, lively, spicy, minerally, light- to medium-bodied; Austria's most popular white wine now very hot in U.S.; has great affinity with fish entrées.
Kerner (Germany)--hardy, aromatic, flavorful variety; does well in very cool regions, such as northern Alto Adige, Italy.
Malagousia (Macedonia, Greece)--very aromatic; quite full-bodied; almost extinct a short time ago, but now one of Greece's most popular varietal whites.
Malvasia, a.k.a. Malmsey (Italy)--quite flavorful, rather full-bodied; the grape is an extremely versatile variety with a long history tracing back to Greek origins. Throughout Italy, a blending wine and varietal wine (particularly good as Malvasia Istriana). Also a fortified wine (Malmsey in Madeira).
Marsanne (Rhône Valley, France)--deeply colored, rich, nutty, honeyed; dry, full-bodied. In the Rhône Valley, a part of white Hermitage, but also in California, Australia, and Switzerland (as Ermitage Blanc).
Moschofilero (Mantinia, Greece)--pronounced mos cho FEEL eh roe; crisp, lively, very floral; a great apéritif white, now popular in U.S.
Müller-Thurgau (Germany)--grapes planted in cool, high-altitude sites make lively, floral, flavorful wines. From Switzerland, but popular mainly in Germany. Also a white wine in Austria, Northern Italy, England, Australia, Czech Republic, and New Zealand. Particularly good versions from Alto Adige, Italy.
Pecorino (Marche, Abruzzo, Italy)--quite full-bodied, spicy, flavorful. Almost extinct; revived in Marche, now becoming popular in Abruzzo.
Pinot Blanc, a.k.a. Pinot Bianco, Weissburgunder (Burgundy, France)--The grape is a clone of Pinot Noir. Now grown in Alsace, France, California, Northern Italy (as Pinot Bianco), Germany and Austria (as Weissburgunder). Very popular, flavorful, light- to medium-bodied wine as Pinot Bianco in Alto Adige.
Roussanne (Rhône Valley, France)--floral, delicate, herbal, high acidity; an important component of white Hermitage and other Rhône whites; increasingly popular as a varietal wine in California, Washington, and Australia.
Sémillon (Bordeaux, France)--viscous, low acid, aromas of lanolin; great blending partner with Sauvignon Blanc in Bordeaux (Bordeaux Blanc and Sauternes--where it's the dominant variety). Made in California, Washington, and very popular in Australia--on its own and with Sauvignon Blanc.
Sylvaner, aka Silvaner (Germany)--fairly neutral in aroma and flavor; popular in Germany, Alsace. Austria, and Alto Adige, Italy. Probably from Austria.
Torrontés (Argentina)--dry, aromatic, spicy, with distinct, Muscat-like flavor; grown throughout Argentina's wine regions. The grape is possibly related to Muscat variety.
Verdelho, a.k.a. Godello (Portugal)--full-bodied, limey, aromatic; now popular in Australia as a dry white, but its history is mainly in Portugal's Douro Valley. Also used in Madeira, and in Loire Valley, France. Possibly originated in Sicily.
Vermentino, a.k.a. Rolle (Spain)--fragrant, full-bodied; now mainly popular throughout Italy as a varietal wine in Tuscany, Liguria, and Sardinia. Also in Corsica and Provence (as Rolle). Increasingly popular in California.
Viognier (Rhône Valley, France)--pronounced vee ohn yay; floral, delicate, apricoty aromas; medium-to full-bodied; low acidity. The variety of Condrieu wine in Northern Rhône; also a varietal wine in southern France and California.
Viura, a.k.a. Macabeo (Spain)--aromatic, fresh, lively; mainly in Rioja region and in northeastern Spain--where it's known as Macabeo and used in cava (Spanish sparkling wine).
Xarel-lo, a.k.a. Xarello (Catalonia, Spain)--pronounced char REL oh; full-bodied, lively, hints of peach or apricot. Mainly used to make cava (Spanish sparkling wine), but increasingly used as a varietal wine in Catalonia.
Agiorgitiko, a.k.a. St. George (Nemea, Greece)--pronounced eye your YEE tee koe; spicy, plum fruit flavors, medium-bodied; low acidity. One of Greece's two most popular varietal red wines. Sometimes blended with Cabernet Sauvignon.
Aglianico (Southern Italy)--originally from Greece, Aglianico's home now is in Basilicata (Aglianico del'Vulture wine) and Campania (Taurasi wine). Full-bodied, high in tannin and acidity; resembles Barolo in structure. Considered Southern Italy's finest red variety. Also in Puglia and in California.
Barbera (Piedmont, Italy)--fruity, high acid, low tannin red wine; versatile with all kinds of food. Popular everyday wine in Piedmont, best known as Barbera d'Alba and Barbera d'Asti. Also grown in California and Argentina.
Blaufränkisch, a.k.a. Lemberger; Kékfrankos (Austria)--dark-colored, tannic, spicy; grown throughout Central Europe. A varietal and blended red wine in Austria, Czech Republic, Germany (where it's known as Lemberger), Slovakia, Slovenia, and Hungary (where it's known as Kékfrankos, an important varietal wine). Also in Washington, where it's Lemberger, a pleasant, spicy wine.
Bonarda (Piedmont, Italy)--light, fruity, easy-drinking; used as a varietal wine in Piedmont and in Oltrepó Pavese (Lombardy, Italy), but now a bigger presence in Argentina (a leading red variety there, along with Cabernet Sauvignon and, from this list, Malbec).
Carignan, a.k.a. Mazuelo (Spain)--high-yielding, warm-climate red with lots of tannin, color, and acidity, used mainly for blending. Found mainly in Southern France. It was France's most-planted red variety, until recently surpassed by Merlot. Also in Northwest Spain, Rioja, and California.
Carmenère (Bordeaux, France)--deep red color, fruity, spicy; soft tannins. Although once important in Bordeaux, now almost all of the world's Carmenère comes from Chile. A little also in California and Walla Walla, Washington.
Corvina (Veneto, Italy)--light-bodied, mild, dry, fruity; the main variety in Valpolicella and Bardolino. Now also being made as a varietal wine in Veneto.
Dolcetto (Piedmont, Italy)--dark-colored, dry, tannic, with moderate acidity. Popular everyday red wine in Piedmont; now being made as a varietal wine in California. At its best when it's young.
Frappato (Sicily, Italy)--cherry red in color and in flavor; light-bodied, fairly high acidity. From southeastern Sicily; used in blending, but also a varietal wine.
Freisa (Piedmont, Italy)--Fruity, dry, light-bodied red; an apéritif wine in Piedmont. Also made as a lightly sparkling red wine.
Galioppo (Calabria, Italy)--dark, tannic, full-bodied; the main red variety of Calabria, in the red Ciró wine.
Gamay (Burgundy, France)--light-bodied, fruity, purple-red; the variety of Beaujolais. Also in the Loire Valley.
Graciano (Rioja, Spain)--deep red color, aromatic, low-yielding. Primarily used as a blending wine in Rioja, but also sometimes a varietal wine.
Grignolino (Piedmont, Italy)--light red, fruity, dry, high in acidity and tannin; makes a delightful apéritif red or rosé wine in Piedmont. Also in California.
Kadarka (Hungary)--full-bodied, aromatic, dark red; Hungary's everyday red varietal wine. Probably originated in Albania. Also grown in Bulgaria.
Lagrein (Trentino-Alto Adige, Italy)--deep-colored, high in acidity and tannin; originated in Alto Adige, around the city of Bolzano, where it mainly grows. The grape is related to Syrah variety. A little is grown in California's Central Coast.
Malbec, a.k.a. Auxerrois, Cot (Bordeaux, France)--dark, tannic, dry, plummy; although from Bordeaux, rarely used there now because of the grape's need for sun and heat. At its best in Cahors (southwestern France) and in Argentina, where it's the leading red variety. Also in Chile, Australia, California, Washington, and Long Island.
Mencia (Spain)--dark-colored, full-bodied, tannic; this variety has experienced a 're-birth' in Bierzo region of northeast Spain; a 'hot' varietal wine, rivaling Priorat.
Montepulciano (Abruzzo, Italy)--deep-colored, tannic; everyday red wine, known as Montepulciano d'Abruzzo; also used in Rosso Cònero wine in Marche. Grown extensively in California. Also in Texas, Maryland, and Australia.
Mourvèdre, a.k.a. Monastrell; Mataró (Rhône Valley, France)--purple-red, tannic; high in acidity and alcohol; used primarily as a blending wine in the Rhône Valley, but is a varietal wine in Provence's Bandol AOC region. Also, a varietal and blending wine in California and Australia. Known as Monastrell in Spain. The variety might have originated in Catalonia, Spain.
Negroamaro (Puglia, Italy)--dark-colored, tannic; Puglia's main red variety. Primary variety in Salice Salentino wine.
Nero d'Avola, a.k.a. Calabrese (Sicily, Italy)--dark-colored, tannic; Sicily's leading red varietal wine. From town of Avola in southeastern Sicily, although Calabria on Italy's mainland argues that it's from their region.
Nerello Mascalese (Sicily, Italy)--medium-bodied, dry, fruity; from the Catania area, primarily grown around Mt. Etna in northeastern Sicily; the main variety in Etna Rosso. Also a varietal wine, along with its lesser-known relative, Nerello Cappuccio.
Petite Sirah, a.k.a. Durif (France)--dark-colored, very tannic; high in acidity; primarily used as a blending wine in California, but has a cult following as a varietal wine. Also, a little in France (as Durif), in Israel, Washington, Australia, Chile, and Mexico's Baja Peninsula.
Petit Verdot (Bordeaux, France)--late-ripening, tannic, very dark red; still used in some Bordeaux blends. Becoming more important in places where climate permits it to ripen more easily, such as California, where it's used in blends and as a varietal wine. Also grown in Australia, New Zealand, Chile, and Argentina.
Primitivo, a.k.a. Zinfandel, Crlijenak Kästelanski (Croatia)--very dark, jammy, full-bodied, high-alcohol variety; although Primitivo and Zinfandel apparently originated on the Dalmatian coast of Croatia (where it's known as Crlijenak Kästelanski), Primitivo is grown mainly in Puglia. Often blended with Negroamaro, but also a varietal wine. Also in California.
Refosco (Friuli-Venezia Giulia, Italy)--deep-colored, tannic, with high acidity; flavors of plums and almonds. Made primarily as a varietal wine in Colli Orientali district of Friuli. Also in Slovenia, Croatia, and Greece. A sub-variety, Refosco dal Peduncolo Rosso, is considered the finest version of Refosco.
Sagrantino (Umbria, Italy)--tannic, highly acidic, full-bodied; formerly made as a sweet wine, now strictly dry. Its finest expression in Umbria is as Sagrantino di Montefalco DOCG wine. A little Sagrantino grows in California.
Tannat (Southwest France)--highly tannic, dark red. Tannat's home is in the foothills of the Pyrenees Mountains in southwest France, where it produces very dark, full-bodied, tannic reds, such as Madiran. Now the main red variety in Uruguay, where it is less tannic. Also grown quite extensively in California, and in Argentina and Australia as well.
Tempranillo, a.k.a. Tinta Roriz, Tinta del Pais (Spain)--dark-colored, full-bodied; Spain's great noble red variety, the main variety in Rioja and Ribera del Duero. Also grown in Chile, Argentina, and lately, in California. In Portugal, known as Tinta Roriz, one of the grapes used in making Port wine.
Teroldego (Trentino-Alto Adige, Italy)--dark-colored, spicy, with high acidity. Made primarily in Trento province as a wine called Teroldego Rotaliano. Also grown in California.
Touriga Nacional (Portugal)--full-bodied, tannic, concentrated; considered Portugal's finest red variety. Probably brought to Portugal by Phoenicians. The most important variety in Port wine; made as a varietal dry wine and as part of a blended wine in northern Portugal as well. Also in California, where it has been used in making domestic port wines.
Xynomavro (Macedonia, Greece)--pronounced ksee NO mav roe; highly tannic; spicy, dark-colored, with high acidity; home is Naoussa district of Macedonia. Northern Greece's most important red variety; has been compared to Barolo.
Zweigelt (Austria)--hardy, cold-climate, spicy red; a cross between Austrian St. Laurent and Blaufränkisch varieties; now Austria's most-planted red variety. Also grown in Canada.
